A question about tenpai?

[or2az]

I have a question about the exact definition of tenpai. Does it mean that you are one tile away from winning or one tile away from having a complete hand, because these two conditions do not seem to be the same thing. For example, Suppose I have the following fictitious hand needing 2 tiles for all simples.

Someone discards a which I accidentally call and expose the chow. Let's say i thought it was a
I discard my and become tenpai, waiting for the or and a share of the 3000 points as the hand now ends in a draw. WHY???
I was not one tile away from winning since I screwed up the hand with the accidental call so why am I entitled to bonus points?

[Kyuu]

http://arcturus.su/wiki/Tenpai

You look at that hand, and ask yourself: What do I need to complete that hand? If you don't know what a complete hand is, you made one in your post.

become tenpai

The hand doesn't become tenpai. It stays at tenpai; your original hand was at tenpai. However, the wait changes.

[or2az]

you are correct . i wrote it wrong. fixed it

[Shirluban]

You are tenpai if you are one tile away to have a complete hand, even without any yaku.
Unless you need five identical tiles to complete the hand, or if you suffer from a "dead hand" penalty.

By the way, an one-away-from-complete hand is also one-away-from-winning.
You can still win with the last hand of the wall, or by robbing a kan, or by making a kan yourself and drawing your winning tile.

[gemma]

You can also use the rule for continuances where you don't need to have a yaku and you only need to be tempai to your advantage. If you're dealer for example, you can do some dirty chiing and poning to get a tempai hand and keep your dealership.

[or2az]

I understand now. Even though the tanyao win was unattainable due to the exposed terminal chow, I could still tsumo or ron the or on the last tile or last discard and win, so technically, every one-away-from-complete hand is one away from winning because you still have that last shot at your winning tile, just with a different yaku, even though this is not very likely to occur.
I guess I am entitled to a share of that 3000 points. Thanks, Shirluban. You too, Gemma.

[or2az]

But wait a minute! What about if all of the tiles you need to win have already been discarded?
Then it would seem that one-away-from-complete is not the same as one away from winning because here it is impossible to win!
Or am I missing something again? Perhaps you are NOT tenpai in this situation?

[Shirluban]

If you're dealer for example, you can do some dirty chiing and poning to get a tempai hand and keep your dealership.

I do that.

But wait a minute! What about if all of the tiles you need to win have already been discarded?

You're still tenpai.
Ok, in this case you may say you're not one away from winning.

[or2az]

I just found posts on this topic from 2009 in the reach mahjong section under "Oh...wait", which you are probably familiar with, and reading them has helped a lot. I see now that one away from a complete hand is the same as one away from winning, except sometimes, its impossible to get that winning tile.